Roland Dreier wrote:> > I am now wondering whether the usage of MSI would help in this case and> > that i should be using enable_msi before request_irq ?> > MSI interrupts are never shared. So if pci_enable_msi() succeeds, you> can be sure that the interrupts you get with that IRQ number are> coming from your device.>

i presume then i shouldn't be using IRQF_SHARED, if using MSI.

Another question would be if the device supports multiple messages, MSIXshould be used ?In such a context, if i request for say more than the messages that ineed, say i request 16 messages, but use only 1 or 2, that does bear anyconsequences ?

> But using MSI does not work on all systems, so your driver needs to> work with standard (possibly shared) INTx interrupts too. And you> should probably provide at least a module flag to disable the use of> MSI, to avoid problems on buggy systems.

I should probably look for CONFIG_PCI_MSI and check whether the systemsupports MSI pci_enable_msi() ?